Polychloroformates



3,051,686 POLYCHLOROFORMATES William E. Bissinger, Akron, Ohio, assignor, by mesne assignments, to Pittsburgh Plate Glass Company No Drawing. Filed Mar. 30, 1960, Ser. No. 18,510 Claims. (Cl. 26077.5)

This invention deals with novel polymers and their manufacture. It more particularly concerns polymers of olefinically unsaturated haloformates, notably chloroformates, and olefins such as ethylene.

The chemical versatility of chloroformate groups or like haloformate groups such as their reactivity with ammonia, amines, alcohols renders them valuable reactants for providing many useful products. Of special interest in this regard are polyfunctional chloroformates, e.g., compounds having a multiplicity of reactive chloroformate groups. Polyfunctional chloroformates, particularly those having three or more chloroformate groups per molecule, are useful in the preparation of three-dimensional polymers by cross-linking through the reactivity of the chloroformate group.

In accordance with this invention, novel polyfunctional interpolymers of unsaturated chloroformates, e.g., allyl chloroformate, and olefins such as ethylene are provided having a multiplicity of reactive chloroformate groups, usually upwards of three and often ten or sometimes fifteen or more. These interpolymers are principally linear in character and have recurring reactive chloroformate groups. Many of the preferred interpolymers have as their principal linear structure a carbon chain including carbon atoms to which are linked through recurring methylene groups reactive chloroformate groups, e.g., the polymers contain the recurring methylchloroformate pendant groups,

By virtue of their polyfunctionality, these polychloroformate polymers are convertible into three-dimensional, thermosetting, cross-linked polymers by reaction with appropriate polyfunctional materials including polyfunctional alcohols and amines. Thus, polyfunctional, usually difunctional, materials such as diols (aliphatic or aromatic) or diamines may be reacted with these polychloroformate polymers in the provision of three-dimensional polymers. The reactivity of the chloroformate and OH or amino groups provides carbonate or carbamate linkages for realizing such cross-linking. Other polymers are prepared from the novel polychloroformate interpolymers by reaction with an alcohol or amine having a polymerizable functionality such as an olefinically un saturated alcohol or amine, or an epoxy alcohol (glycidol) and polymerization of the reaction products via the unsaturation or other polymerizable functionality provided from the alcohol or amine.

Three-dimensional polymers, above described, are useful in providing surface finishes. They thus may be used to coat protectively various surfaces such as wood, metal including iron, copper and steel, natural and synthetic cellulosic sheeted and Woven materials such as paper, cotton textiles and the like, by efiecting in situ the conversion of the polychloroformate or a polymerizable derivative thereof to three-dimensional polymers.

Preferred polychloroformate interpolymers are those of allyl chloroformate and ethylene. Among such interpolymers are those which contain from about 5 to 85 percent allyl chloroformate moieties by Weight and have chloroformate chlorine contents ranging from 1 to 25 weight percent. Their cryoscopic molecular weights typically vary from 500 to 3500.

Of these interpolymers, those having more than about ice By reaction with compounds having polyfunctional reactivity with respect to chloroformate groups, three-dimensional, thermosetting polymer are prepared.

Thus, using dihydroxy compounds, the interpolyrners of allyl chloroformate and ethylene are cross-linked yielding three-dimensional polymers having as an identifying configuration:

wherein R denotes the residue of the dihydroxy com-' pound. At least one such cross-linking structure is pres ent, and usually most of the polymers include a multiplicity thereof corresponding approximately to the number of chloroformate groups present in the copolymer. These three-dimensional polymers may, accordingly, be described as polyesters of (a) a biscarbonic acid of a dihydroxy compound and (b) a polyhydric interpolymer' of allyl alcohol and ethylene.

Dihydroxy compounds (or diols) include glycols such as diethylene glycol, ethylene glycol, propylene glycol, polyalkoxy glycols, etc.; xylylene glycols, catechol, resorcinol, and the alkylidene bisphenols, e.g., Bisphenol A.

With reactive diamines (e.g., those having available hydrogens linked to two of their amino nitrogens), the cross-linking structure is representable as:

I II I I I II I R denoting the residue of a diamine among which are ethylene diamine, isopropylene diamine, trimethylene diamine, piperazine, hexamethylene diamine, diarninobenzenes, toluene diamine, alkylidene dianilines, and the like. Cross-linking is achieved by virtue of two carbamate groups and the three-dimensional polymers may be regarded as polyesters of (a) a dicarbamic acid and (b) a polyhydric interpolymer of ethylene and allyl alcohol wherein hydroxyl groups'of the interpolymer are esteritied with carbamic acid groups.

Mixed esters of carbonic and carbamic acids are obtained through the use of compounds having both amine and hydroxyl functionality such as ethanolamine and diethanolamine. For example, by reaction of ethanolamine with the polychloroformate, there is formed a polymer having a cross-linking structure representable as:

More complex polymers of the polychloroformates result from their reaction with trifunctional, tetrafunc-tional, etc., alcohols, amines or mixed alcohol-amines as illustrated by glycerin, trimethylolethane, pentaerythritol and diethanolamine.

Besides OH and amino groups, the polychloroformate polymers are reactive with other compounds having polyfuuctional reactivity with respect to chloroformate groups to yield cross-linked polymers. Such compounds (including polymeric materials) are those containing a plurality of groups" having active hydrogen (a hydrogen of the type which is linked direetly to a nitrogen, sulfur or oxygen atom) and include besides those already mentioned mercaptar'is corresponding to the diols such as 1,2-ethainedithiol. I

The interpolymers herein contemplated including the referred interpolymers of ethylene and allyl chloroformate are prepared by interpolymerizing an olefin and a chloroformate of an unsaturated alcohol, usually in a liquid diluefli under Pressure a With the aid of a catalyst Such unsaturated group, preferably olefinic unsaturation, and as diisopropyl peroxydicarbonate 01- like esters such as an alcoholic hydroxyl group attached to an aliphatic are described in United States Letters Patent 2,370,588, carb n, granted ry l Olefins c a e hylen r Interpolymers of unsaturated chloroformates and olenormally gaseous and hence copolymerizatlon 1S 6011- finically unsaturated materials other than ethylene are ducted by recourse to a liquid diluent in which the olefin contemplated, Th th l may b i ll or 1s dissolved. pletely replaced by propylene, butadiene, butene-l, bu- The following examples 1llustrate the copolymenzation time-2, isobutylene, pentene-l, 2-methylbutene-l, hexof ethylene and allyl chloroforrnate to produce polychlon -l, m m -1, t acrylonjtrfle, b way f m roformate polymers. tration.

Example I 'lnterpolymer polychloroformsates so provided may be A series of ethylene-allyl chloroformate interpolymers converted i three'dun"jnS1na1 Polymers hlgher are prepared by mixing allyl, chloroformate, anhydrou leoular werght products in the manner here1n described benzene (thiophene free) and diisopmpyl peroxydicar 1n deta1l with respect to allyl chloroformate-ethylene 1nbonate in a glass-lined autoclave having a capacity of 300 y e milliliters in amounts as listed in Table I. The autoclave 3O As mdlcat?d b the details glven m the expenment the contents are flushed twice with high purity ethylene (99,5 interpolymenzanon of the chloroformate of an unsanipercent pure ethylene except in Run B where it was 99.9 Tated a1ch1 Such alcohol and ethylene 11156 percent pure ethylene) to displace air, then rocked olefinlc hydrocarbon 1s 1n1t1 ated by recourse to certain fined with ethylene at full. Superatmosphefic cylinder catalysts exemplified by 1sopropyl peroxydicarbonateand pressure atroom temperature (about Aft the other peroxydwarbonate esters heretofore mentioned. contents of the autoclave are saturated with ethylene, the Qther free f f lIlltlatOrS 911 as benzoyl chlonde, azocontents of the closed autoclave are gradually raised by l'sobutyromtrfle acetyl Peroxlde: t'butyl Peroxlde, heating over a period of 30 minutes to the temperature also used; specified in Table I. With rising temperatures, pressure 40 Formatlol} 'P P P Wlth most faculty increases. As the reaction proceeds, additional ethylene an orgamc hquld f ga solvents for P is added Whenever superannospheric pressure drops reactants are thus employed 1n providing a proper react1on low the initial full cylinder pressure. med um. Moreover, since the 1nterpolymers are at least After no f th decrease inopressure is observed, the sparmgly soluble in benzene and often reasonably soluble autoclave contents are allowed to cool to room temperabenzene other 9101931105, arPmatlc Solvents, espeture and the contents treated to separate solvent, any claHY Wlth PP QP cham transfer constaflts, unreacted monomer and other materials by heating the Rwvlde SUI/[able medla 111 whfch conduct P y ti mixture under nitrogen to 40 C at 4 n t1on. However, other essentially inert organic liquids, meters f mercury vacuum especially those in wh1ch the reactants are adequately The following Table I lists the details of various p soluble, 1nclude chlorinated aliphatic hydrocarbons such arations of copolymers in accordance with the foregoing as methylene chloride, dichloroethane, hydrocarbons inprocedure: eluding cyclohexane, toluene, heptane, octane, etc.

Table I Pressure, 551g. Product ACE, IPP, Benzene, Tempera- Run grams grams milllture, C. Chloro- Molecu- Weight Average liters Yield, iormate lar Percent Number- Inltial Maximum grams Chlorine, Weight AOF ln Nature ofACF Percent Polymer Units per hain 20. 3 2. 2 72 690 830 53 27. 7 12. 3 2, 275 41. 8 7. 9 20. 3 2. 2 72 700 975 53 35.1 11.8 2,080 40.1 7. 0 20. 3 2. 2 72 650 730 40 31.1 12. 0 1, 915 40. 7 6. 6 20.3 4.4 72 630 830 53 32.3 10.9 2,900 37.0 o 8.9 5.7 2.2 670 820 53 25.1 4.8 2,470 15.3- white waxy so1id 3.3 3.4 2.2 87 600 830 53 19.1 1.7 5.8 O 51.9 7.3 239 875 5(40") 40-50 117.0 10.8 2,190 35.7 yellowish white 6.7

0 (50) semi-solid. 21.1 6.8 261.3 740 2, 35 2; 40-50 114.5 3.8 11.2 white powder 1 126.6 6.8 168 740 800 (40) 40-50 132.7 18.1 2,070 61.4 viscous 11 m"--. 10.6

1 AOF denotes allyl chloroformate.

1 IPP denotes lsopropyl peroxydlcarbonate.

B As determined by cryoscoplc method in benzene. 4 Autoclave capacity 1000 milliliters.

Superatrnospheric pressures are imposed upon the liquid medium in which polymerization is conducted, especially when using a gaseous monomer, notably the olefin monomer. Depending upon the temperature at which polymerization is conducted, the particular solvents and particular olefins, etc., considerable variation in superatmospheric pressure is possible. As a rule, pressures in excess of about 600 pounds per square inch gauge up to 5000 pounds per square inch gauge or somewhat higher are typical of those used most often. This, however, does not preclude the use of still higher pressures, although practicalities rarely dictate recourse to unusually high pressures.

Polychloroformate interpolymers of an unsaturated chloroformate rand olefinic hydrocarbon (or olefinic chlorohydrocarbon) are reactive with monohydroxy or dihydroxy compounds, either saturated or unsaturated, amines and diamines, ammonia, pyridine, sodium hydroxide, or like alkalis, to produce polymeric materials having a plurality of carbonate and/ or carbmate groups. Thus, reaction of the polychloroformate intenpolymers here provided with a hydroxy compound such as an alcohol yields polycarbonates. A polymerizable polycarbonate having polymerizable olefinic unsaturation is attained by reaction of the polychloroformate polymer with an unsaturated polymerizable alcohol such as allyl alcohol. The resulting polycarbonates are useful as casting resins in the formation of optically clear plastic sheets such as are useful in lieu of glass where the breakability of glass is undesirable. Other polymerizable polycarbonates are attainable by reaction of glycidol (or epoxy alcohols) with the polychloroformate. They are polymerizable via their multiplicity of epoxy groups.

The following example illustrates the manner in which polychloroformate polymers are converted into polymerizable polycarbonates:

EXAMPLE II Some 2 moles of redistilled alcohol, 0.7 mole of pyridine, and 250 cubic centimeters of redistilled toluene are placed in a round bottom glass reaction flask equipped with a mechanical stirrer, a thermometer and a dropping funnel. To this well stirred solution maintained at a temperature of about 8 C., a toluene solution containing 98 grams of the interpolymer of Run I in Table I is added. After completing the addition and stirring overnight, the reaction medium is Water washed using sodium carbonate to reduce emulsification. Some 78.6 grams of a viscous yellow liquid polycarbonate having a chloroformate chlorine content of about .2 percent by weight and a C0 content of 21.4 percent by weight are obtained. The olefinic unsaturation content of this polycarbonate determined as allyl alcohol is 29.1 weight percent.

A casting of this polycarbonate is prepared by curing (or further polymerizing) the polycarbonate for 72 hours at 70 C. in the presence of 5 percent by weight of benzoyl peroxide. A white opaque solid of substantial surface hardness was obtained.

Besides polymerizing olefinically unsaturated chloroformates and olefin hydrocarbons, olefin halohydrocarbons and especially olefin chlorohydrocarbons give rise topolychloroformate polymers containing substantial chlorine other than chloroformate chlorine. The presence of this chlorine in the polymer renders it flame resistant and hence useful for reaction with alcohols, amines and the like in the formation of higher molecular weight polymers suitable for imparting flame resistance. These higher molecular weight polymers may be employed to impregnate textiles such as Woven cotton, wools and the like to impart flame resistant properties.

The following example illustrates the copolymerization of an olefin chlorohydrocarbon and an olefinically unsaturated chloroformate:

5 EXAMPLE III A round bottom glass flask fitted with a condenser closed with a vent is charged with 41.3 grams (0.314 mole) of trichloroethylene, 27.2 grams (93.2 percent by weight pure, 0.209 mole) of allyl chloroformate and 1.2 grams of isopropyl peroxydicarbonate. After the flask is flushed with nitrogen, its contents are heated to 45 C. for a period of 77 hours.

The interpolymer is recovered from the resulting re action medium in the amount of 34.4 grams by subjecting the reaction mixture to vacuum distillation under a nitrogen path using a pot temperature of 65 C. and 3 millimeters of mercury pressure.

The cryoscopic molecular weight in benzene of this polymer is 625. Its chloroformate chlorine content is 18.2 percent by weight .and it contains a total of 48.2 percent chlorine. Some 61.8 percent by weight of the polymer is provided by the allyl chloroformate monomer. The copolymer is readily soluble in benzene.

In general, the better copolymers of olefinic chlorohydrocarbons and unsaturated chloroformate, e.g., those containing higher chlorine contents, are attained by employing some 60 parts by weight of the chlorohydrocarbon basis 100 parts by weight of the two monomers.

Besides trichloroethylene, other olefinic halohydrocarbons including mixed halohydrocarbons, e.g., chlorofluorohydrocarbons, may be copolymerized with unsaturated chlcroformates to provide useful polymeric materials. Other olefinic halohydrocarbons which may be mentioned include the dichloroethylenes (cis and trans), 1,1- dichloro 2 fiuoroethylene, 3,3,3 trichloro 1 propene, 1,2-difluoroethylene, and longer carbon chain halohydrocarbons, usually including those having up to eight aliphatic carbons.

While the present invention has been described by reference to specific details of certain embodiments, it is to be understood that it is not intended that the invention be construed as limited to such details except insofar as these details appear in the appended claims.

I claim:

1. An interpolymer of (A) an olefinically unsaturated chloroformate and (B) a compound selected from the group consisting of aliphatic olefinically unsaturated hydrocarbons and aliphatic olefinically unsaturated halohydrocarbons, said interpolymer containing a multiplicity of reactive chloroformate groups and containing from 5 to 85 percent olefinically unsaturated chloroformate moieties, by Weight, based upon the combined Weight of said (A) olefinically unsaturated chloroformate moieties and of (B) said compound selected from said group.

2. An interpolymer of (A) a monoolefinically unsaturated chloroformate and (B) a compound selected from the group consisting of aliphatic olefinically unsaturated hydrocarbons and aliphatic unsaturated halohydrocarbons, said interpolymer containing a multiplicity of reactive chloroformate groups and containing from 5 to 85 percent monoolefinically unsaturated chloroformate moieties, by weight, based upon the combined weight of said (A) monoolefinically unsaturated chloroformate moieties and of (B) said compound selected from said group.

3. An interpolymer of (A) allyl chloroformate and (B) ethylene, said interpolymer containing a multiplicity of reactive chloroformate groups and containing from 5 to 85 percent allyl chloroformate moieties, by Weight, based upon the combined Weight of said (A) allyl chloroformate moieties and of said (B) ethylene.

4. An interpolymer of (A) allyl chloroformate and (B) ethylene, said interpolymer containing from 1 to 25 percent by Weight of chloroformate chlorine and containing from 5 to 85 percent allyl chloroformate moieties, by weight, based upon the combined Weight of said (A) allyl chloroformate moieties and of said (B) ethylene.

5. An interpolymer of (A) a monoolefinically aliphatic unsaturated chloroformate and (B) an aliphatic 7 8 olefinically unsaturated halohydreca-rbon having up to 8 References Cited in the file of this patent carbon atoms, said interpolymer containing a multiplicity UNITED STATES PATENTS a: it f i t g iolgtammg fi i g; 2,377,085 Kung May 29, 1945, P n mono) emca Y 1P a a 2,440,090 Howk et a1. Apr. 20, 1948 chloroformate moieties, by Weight, based upon the com- 5 2,464,056 Pechukas Man 8, 1949 bined weight of said (A) monoolefinically aliphatic unsaturated chloroformate moieties and of said aliphatic FOREIGN PATENTS olefinically unsaturated halohydrocarbon. 522,654 Canada Mar. 13, '1956 

1. AN INTERPOLYMER OF (A) AN OLEFINICALLY UNSATURATED CHLOROFORMATE AND (B) A COMPOUND SELECTED FROM THE GROUP CONSISTING OF ALIPHATIC OLEFINICALLY UNSATURATED HYDROCARBONS AND ALIPHATIC OLEFINICALLY UNSATURATED HALOHYDROCARBONS, SAID INTERPOLYMER CONTAINING A MULTIPLICITY OF REACTIVE CHLOROFORMATE GROUPS AND CONTAINING FROM 5 TO 85 PERCENT OLEFINICALLY UNSATURATED CHLOROFORMATE MOIETIES, BY WEIGHT, BASED UPON THE COMBINED WEIGHT OF SAID (A) OLEFINICALLY UNSATURATED CHLOROFORMATE MOIETIES AND OF (B) SAID COMPOUND SELECTED FROM SAID GROUP. 